Tool assemblies with a gap locking member

ABSTRACT

A tool assembly includes an anvil and a cartridge assembly movable from an open position to a closed position, and a locking member movably supported on a distal portion of the cartridge assembly. The locking member is configured to move into a slot of the anvil as the anvil and cartridge assembly move toward the closed position to set a gap distance between the anvil and cartridge assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of U.S. patent applicationSer. No. 16/789,746, filed on Feb. 13, 2020, which claims the benefit ofand priority to U.S. Provisional Patent Application No. 62/817,807,filed on Mar. 13, 2019, the entire contents of each of which beingincorporated by reference herein.

BACKGROUND 1. Technical Field

This disclosure is directed to a surgical stapling device and, moreparticularly, to a tool assembly of a surgical stapling device thatdefines a tissue gap and includes a locking member to maintain thetissue gap during firing of the tool assembly.

2. Background of Related Art

Surgical stapling devices are commonly used during a variety of surgicalprocedures to staple and/or cut tissue. Stapling and cutting of tissuecan be accomplished more quickly using surgical stapling devices thancan be accomplished using traditional suturing techniques. In addition,endoscopic stapling devices can be used to perform less invasivesurgical procedures than possible using traditional suturing techniques.As such, the use of surgical stapling devices to perform certainsurgical procedures to reduce patient trauma and improve patientrecovery times is desirable.

Typically, linear endoscopic surgical stapling devices include a toolassembly that includes a staple cartridge and an anvil assembly that aremovable in relation to each other between open and clamped positions.The staple cartridge defines a plurality of staple pockets that receivestaples and the anvil assembly defines a plurality of staple deformingpockets. When the tool assembly is in the clamped position, the stapledeforming pockets of the anvil assembly are aligned with the staplepockets of the staple cartridge such that legs of the staples arereceived and deformed within the staple deforming pockets when thestapling device is fired. The staple cartridge and the anvil assemblymust be properly aligned to effect proper staple formation.

Generally, the staple cartridge and the anvil assembly have proximalends that are secured to each other by a pivot member such that thestaple cartridge and the anvil assembly can be pivoted from the openposition in which distal ends of the staple cartridge and the anvilassembly are spaced from each other to the clamped position in which thestaple cartridge and the anvil assembly are in juxtaposed alignment.During firing of the staples from the staple cartridge, forces on thestaple cartridge and the anvil assembly for firing the staples tend todeflect the staple cartridge and anvil assembly outwardly away from eachother. In certain stapling devices, a knife bar is provided thatincludes upper and lower beams that engage the anvil assembly and staplecartridge to minimize deflection of the anvil and cartridge assembliesduring firing.

SUMMARY

One aspect of this disclosure is directed to a tool assembly includingan anvil, a cartridge assembly, and a locking member. The anvil and thecartridge assembly each have a proximal portion and a distal portion.The proximal portion of the cartridge assembly is movably coupled to theproximal portion of the anvil. The distal portion of the anvil defines afirst slot therein. The locking member is movably supported on thedistal portion of the cartridge assembly. The locking member isconfigured for receipt in the first slot of the anvil to set a gapdistance between the anvil and cartridge assembly when the anvil andcartridge assembly are in the closed position.

In aspects, the locking member may include a first latch arm configuredfor receipt in the first slot of the anvil when the anvil and cartridgeassembly are in the closed position.

In aspects, the first latch arm may have an extension configured to becaptured in the first slot of the anvil when the first latch armdistally translates.

In aspects, the locking member may include a second latch arm. The firstand second latch arms may be disposed on opposite lateral sides of thecartridge assembly.

In aspects, the distal portion of the anvil may define a second slottherein configured for receipt of the second latch arm of the lockingmember.

In aspects, the first and second slots may be disposed on oppositelateral sides of the anvil.

In aspects, the tool assembly may further include a clamping memberoperably coupled to the proximal portion of each of the anvil andcartridge assembly and configured to move the anvil and cartridgeassembly from an open position to a closed position. The locking membermay be configured to be coupled to the clamping member, such thatadvancement of the clamping member moves the locking member into thefirst slot of the anvil to set a gap distance between the anvil andcartridge assembly.

In aspects, the locking member may include an elongate element and afirst latch arm. The elongate element may have a proximal end portionconfigured to be coupled to the clamping member. The first latch arm mayextend upwardly from a distal end portion of the elongate element. Thefirst latch arm may be configured to translate distally into the firstslot of the anvil in response to advancement of the clamping member.

In aspects, the clamping member may have a distally-extending latchmember configured to couple to the proximal end portion of the elongateelement of the locking member upon the anvil and cartridge assemblymoving to the closed position.

In aspects, the latch member of the clamping member may have aprotrusion, and the proximal end portion of the elongate element of thelocking member may define an opening configured for removable receipt ofthe protrusion.

In aspects, the tool assembly may further include a sled slidablyreceived in the cartridge assembly and configured to move from aproximal position to a distal position to advance staples from thecartridge assembly. The sled may be operably coupled to the clampingmember, such that advancement of the sled from the proximal positiontoward the distal position distally translates the locking member.

In aspects, the tool assembly may further include an elongate plateslidably coupled to the cartridge assembly. The elongate plate maydefine a proximal slot in a proximal end portion of the elongate plate,and a distal slot in a distal end portion of the elongate plate. Theclamping member may be received in the proximal slot and the lockingmember may be received in the distal slot.

In aspects, the locking member may be configured to lockingly engage thefirst slot in the anvil in response to advancement of the elongate plateby the clamping member.

In aspects, the locking member may be an I-beam having a bottom endportion received in the distal slot of the elongate plate, and a top endportion configured for receipt in the first slot of the anvil.

In aspects, the elongate plate may be configured to advance relative tothe locking member a predetermined distance prior to engaging andadvancing the locking member.

In aspects, the locking member may be pivotably supported by the distalportion of the cartridge assembly and configured to pivot into lockingengagement with the slot as the anvil and cartridge assembly move towardthe closed position.

In aspects, the tool assembly may further include a biasing membercoupled to the locking member for resiliently biasing the locking membertoward a locking position.

In aspects, the distal portion of the anvil may have a cam surface and asupport ledge. The cam surface may be configured to pivot the lockingmember out of the locking position as the anvil and cartridge assemblymove toward the closed position. The biasing member may be configured topivot the locking member toward the locking position and onto thesupport ledge when the anvil and cartridge assembly enter the closedposition.

In aspects, the locking member may include a top end portion includingan extension configured to be supported on the support ledge of theanvil to prevent the anvil and cartridge assembly from moving out of theclosed position. The locking member may include a bottom end portionpivotably supported in the cartridge assembly and coupled to the biasingmember.

In another aspect of the disclosure, a tool assembly is provided andincludes an anvil and a cartridge assembly each having a proximalportion and a distal portion. The proximal portion of the cartridgeassembly is movably coupled to the proximal portion of the anvil. Thedistal portion of the anvil defines a slot therein. The tool assemblyincludes a clamping member and a locking member. The clamping member isoperably coupled to the proximal portion of each of the anvil andcartridge assembly and configured to move the anvil and cartridgeassembly from an open position to a closed position during a firstadvancement of the clamping member. The locking member is slidablysupported on the distal portion of the cartridge assembly. The lockingmember is configured to be coupled to the clamping member upon the anviland cartridge assembly moving to the closed position, such that a secondadvancement of the clamping member advances the locking member intolocking engagement with the slot of the anvil to set a gap distancebetween the anvil and cartridge assembly.

As used herein, the terms parallel and perpendicular are understood toinclude relative configurations that are substantially parallel andsubstantially perpendicular up to about + or −10 degrees from trueparallel and true perpendicular.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the disclosed linear surgical stapling deviceincluding a tool assembly are described herein below with reference tothe drawings, wherein:

FIG. 1 is a side perspective view of an exemplary embodiment of thedisclosed staple reload including a tool assembly in an open position;

FIG. 2 is an exploded perspective view of the tool assembly shown inFIG. 2 including a drive assembly;

FIG. 3A is a perspective view of a first side of components of the driveassembly of FIG. 2 illustrating first and second drive shafts of thedrive assembly coupled to one another;

FIG. 3B is a perspective view of a second side of the components of thedrive assembly of FIG. 3A;

FIG. 4 is a longitudinal cross-sectional view of the drive assembly ofFIG. 3A illustrating a connector pin coupling the first and secondfiring shafts;

FIG. 5 is a longitudinal cross-sectional view of the drive assembly ofFIG. 3A illustrating the connector pin disengaged from one of the firingshafts;

FIG. 6 is an enlarged perspective view of the tool assembly shown inFIG. 1 in the open position;

FIG. 7 is an enlarged perspective of the area of detail “7” indicated inFIG. 6 ;

FIG. 8 is an enlarged perspective of the area of detail “8” indicated inFIG. 6 ;

FIG. 9 is a perspective view of a channel and locking member of acartridge assembly of the tool assembly shown in FIG. 2 ;

FIG. 10 is a perspective view of a clamping member and locking member ofthe cartridge assembly shown in FIG. 1 illustrated in a decoupled state;

FIG. 11 is a side perspective view of the tool assembly shown in FIG. 1illustrating the locking member in a non-locking position;

FIG. 12 is an enlarged perspective view of the area of detail “12” shownin FIG. 11 illustrating the clamping member engaged to the lockingmember;

FIG. 13 is a top perspective view of the tool assembly of FIG. 1illustrated in a closed position with the locking member shown in alocking position;

FIG. 14 is a bottom perspective view of the tool assembly of FIG. 13 ;

FIG. 15 is a longitudinal cross-sectional view of another exemplaryembodiment of a tool assembly including a clamping member, an elongatelocking plate, and a locking member;

FIG. 16 is a longitudinal cross-sectional view of the clamping member,the elongate locking plate, and the locking member shown in FIG. 15 ;

FIG. 17 is a perspective view of the locking member of FIG. 15 ;

FIG. 18 is a longitudinal cross-sectional view of the tool assembly ofFIG. 15 illustrating the locking member in a non-locking position;

FIG. 19 is a longitudinal cross-sectional view of the clamping member,the elongate locking plate, and the locking member of FIG. 18illustrating the elongate locking plate in an advanced position;

FIG. 20 is a longitudinal cross-sectional view of the tool assembly ofFIG. 15 illustrating the clamping member, the elongate locking plate,and the locking member in a locking position;

FIG. 21 is a longitudinal cross-sectional view of the tool assembly ofFIG. 15 illustrating the locking member in a retracted position;

FIG. 22 is a longitudinal cross-sectional view of the clamping member,the elongate locking plate, and the locking member of FIG. 21 ;

FIG. 23 is a longitudinal cross-sectional view of another exemplaryembodiment of a tool assembly including a locking member illustratingthe tool assembly shown in an open position;

FIG. 24 is longitudinal cross-sectional view of a distal end portion ofthe tool assembly of FIG. 23 with the tool assembly in a partiallyclosed position and the locking member making an initial contact with ananvil;

FIG. 25 is a longitudinal cross-sectional view of the tool assembly ofFIG. 23 with the tool assembly in a fully closed position and thelocking member lockingly engaged to the anvil; and

FIG. 26 is a longitudinal cross-sectional view of the tool assembly ofFIG. 23 illustrating the locking member disengaged from the anvil.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the disclosed tool assemblies will now be described indetail with reference to the drawings in which like reference numeralsdesignate identical or corresponding elements in each of the severalviews. However, it is to be understood that the disclosed embodimentsare merely exemplary of the disclosure and the present tool assembliesmay be embodied in various forms. Well-known functions or constructionsare not described in detail to avoid obscuring the disclosure inunnecessary detail. Therefore, specific structural and functionaldetails disclosed herein are not to be interpreted as limiting, butmerely as a basis for the claims and as a representative basis forteaching one skilled in the art to variously employ the disclosure invirtually any appropriately detailed structure.

The present disclosure provides a tool assembly including a lockingmember movably supported in a cartridge assembly of the tool assembly.An anvil of the tool assembly defines a slot in a distal end portion ofthe anvil. The locking member is positioned for receipt in the slot ofthe anvil when the tool assembly is approximated about tissue a selecteddistance. The locking member is configured to selectively lock the anviland cartridge assembly to maintain a gap distance between distal ends ofthe anvil and cartridge assembly before, during, and/or after staplesare fired from the tool assembly.

In this description, the term “proximal” is used generally to refer tothat portion of the device that is closer to a clinician, while the term“distal” is used generally to refer to that portion of the device thatis farther from the clinician. In addition, the term “clinician” is usedgenerally to refer to medical personnel including doctors, nurses, andsupport personnel.

In FIG. 1 , a staple reload is illustrated generally as staple reload 10and is configured to be coupled to a handle assembly (not shown) of asurgical stapling device, such, as for example, a linear or curvedsurgical stapling device. In aspects, the staple reload 10 may beincorporated into and actuated by a robotic surgical system. The staplereload 10 generally includes a proximal body portion 18 and a toolassembly 20. The tool assembly 20 is articulatable relative to theproximal body portion 18 from a position aligned with a longitudinalaxis “X” defined by the proximal body portion 18 to a positionmisaligned with the longitudinal axis “X.” The tool assembly includes ananvil 34 and a cartridge assembly 36 pivotably coupled to the anvil 34.

With reference to FIGS. 2-5 , the staple reload 10 also includes a driveassembly 22 that includes a first, resilient firing shaft 24 supportinga sled 26 and a second, resilient firing shaft 28 supporting a clampingmember 30. The first and second firing shafts 24, 28 each have aproximal end portion 24 a, 28 a and a distal end portion 24 b, 28 b. Theproximal end portion 24 a of the first firing shaft 24 is configured tobe operably coupled to a drive rod 33 (FIG. 3B) for translating thefirst firing shaft 24 through the proximal body portion 18. The distalend portion 24 b of the first firing shaft 24 abuts, is formed with, oris otherwise coupled to the sled 26 for translating the sled 26 throughthe cartridge assembly 36. As known in the art, the first firing shaft24 can be moved from a retracted position to an advanced position toadvance the actuation sled 26 through the tool assembly 20 tosequentially eject staples into tissue clamped by the tool assembly 20.

The distal end portion 28 b of the second firing shaft 28 abuts, isformed with, or is otherwise coupled to the clamping member 30 formoving the clamping member 30 between proximal and distal positions forrespectively opening and closing the tool assembly 20. The second firingshaft 28 may be fabricated from a pair of elongated laminates. Inaspects, the second firing shaft 28 may be a monolithic structure. Theclamping member 30 is configured to advance with the second firing shaft24 the length of a slot 32 in the anvil 34 to close the tool assembly20.

The proximal end portion 24 a, 28 a of each of the first and secondfiring shafts 24, 28 defines a pin hole 24 c, 28 c having receivedtherein a connector pin 38 for detachably connecting the first andsecond firing shafts 24, 28 to one another. When the pin 38 is receivedin each hole 24 c, 28 c of the first and second firing shafts 24, 28(FIGS. 3B and 4 ), advancement of the first firing shaft 24 drives aconcomitant advancement of the second firing shaft 28. The pin 38 has ahead 38 a received in longitudinally-extending cutout 40 defined in aninner surface of the proximal body portion 18. The head 38 a of the pin38 is biased laterally into the cutout 40 and away from the first andsecond firing shafts 24, 28 by a biasing member 42 (e.g., a coilspring).

The cutout 40 has a proximal section 40 a, and a distal section 40 brecessed at a greater depth than the proximal section 40 a. As the firstand second firing shafts 24, 28 move distally a predetermined distance,corresponding with a closing of the tool assembly 20 by the clampingmember 30, the pin 38 moves from the proximal section 40 a of the cutout40 toward the distal section 40 b of the cutout 40. Due to the biasexerted on the head 38 a of the pin 38 by the biasing member 42, the pin38 is urged laterally into the distal section 40 b of the cutout 40(FIG. 5 ), whereby a tail end 38 b of the pin 38 exits the hole 24 c inthe first firing shaft 24. With the pin 38 no longer engaged to both thefirst and second firing shafts 24, 28, continued advancement of thefirst firing shaft 24 fails to result in further advancement of thesecond firing shaft 28. As such, the sled 26 (FIG. 2 ) of the driveassembly 22 may advance through the tool assembly 20 to eject staplesinto tissue while the clamping member 30 is maintained in a positionproximal of the tissue-engaging surfaces of the anvil 34 and cartridgeassembly 36.

FIGS. 1, 2, and 6 illustrate the tool assembly 20 which includes theanvil 34 and cartridge assembly 36 movably coupled to one another. Eachof the anvil 34 and the cartridge assembly 36 includes a proximalportion 34 a, 36 a and a distal portion 34 b, 36 b. The proximal portion34 a of the anvil 34 is coupled to the proximal portion 36 a of thecartridge assembly 36 such that the tool assembly 20 can pivot betweenan open position (FIG. 1 ) and a closed position (FIG. 11 ). Inembodiments, the cartridge assembly 36 includes a channel 44 (FIG. 2 )that defines a longitudinal slot 46 and a staple cartridge 48 having atissue contact surface 50. The staple cartridge 48 defines a pluralityof staple pockets 52 and is received within the longitudinal slot 46 ofthe channel 44. In some embodiments, the staple cartridge 48 is adaptedto be released from the channel 44 after firing of the tool assembly 20and replaced with a new or loaded staple cartridge 48. Each of thestaple pockets 52 is configured and dimensioned to receive a staple 54.In embodiments, the staple cartridge 48 has a tissue guide portion 56that is angled away from the anvil 34 in the distal direction.

The anvil 34 defines a tissue engaging surface 58 and includes a distalend portion 34 b that is angled from the tissue engaging surface 58 ofthe anvil 34 towards the cartridge assembly 36 at an obtuse angle. Theangled distal end portion 34 b of the anvil 34 forms a dissecting tip60. In embodiments, the dissecting tip 60 is spaced from the tissueguide portion 56 of the staple cartridge 48 when the tool assembly 20 isin the clamped position and extends along an axis that is substantiallyparallel to an axis defined by the tissue guide portion 56. Alternately,the dissecting tip 60 may have other configurations.

With reference to FIGS. 2 and 6-10 , the distal end portion 34 b of theanvil 34 defines a first slot 62 and a second slot 64 (FIG. 13 ) inrespective first and second lateral sides 66 a, 66 b of the anvil 34.Since the first and second slots 62, 64 are configured the same orsimilarly, only the first slot 62 will be described in detail. The firstslot 62 may be formed as a cutout in the first lateral side 66 a of theanvil 34 and has a transverse opening 68 (FIG. 7 ) oriented toward thecartridge assembly 36, and a longitudinal section 70 in communicationwith the transverse opening 68. The first lateral side 66 a of the anvil34 has a support ledge 72 that partially defines the longitudinalsection 70 of the first slot 62.

The cartridge assembly 36 further includes a locking member 74positioned in a groove 76 (FIG. 9 ) defined in an outer surface of thechannel 44 of the cartridge assembly 36 and is slidable therein alongthe longitudinal axis of the cartridge assembly 36. The locking member74 includes an elongate element 78 and a pair of first and second latcharms 80, 82 protruding perpendicularly from a distal end portion 78 b ofthe elongate element 78. The elongate element 78 has a proximal endportion 78 a configured to be coupled to the clamping member 30. Inparticular, the proximal end portion 78 a of the elongate element 78 hasan appendage 84 defining an opening 86 therein configured for removablereceipt of a portion of the clamping member 30, as will be described.

As best shown in FIG. 10 , the clamping member 30 has a latch member 88extending distally from a bottom end portion thereof. The latch member88 of the clamping member 30 has a protrusion 90 extending downwardlytherefrom and configured for removable receipt in the opening 86 in thelocking member 74 when the tool assembly 20 is in the closedconfiguration, such that advancement of the clamping member 30 causesadvancement of the locking member 74.

The first and second latch arms 80, 82 of the locking member 74 extendaround the outer surface of the channel 44 of the cartridge assembly 36and are respectively disposed on opposite lateral sides of the cartridgeassembly 36. Each of the first and second latch arms 80, 82 has ahook-shaped extension 92, 94 protruding inwardly. The extension 92, 94of the first and second latch arms 80, 82 are configured for receipt inthe respective first and second slots 62, 64 of the anvil 34 upon thetool assembly 20 moving to the closed position. The extension 92, 94 ofthe first and second latch arms 80, 82 are configured to cooperativelygrasp the anvil 34 therebetween to prevent the anvil 34 and cartridgeassembly 36 from separating from the closed position.

In operation, when the staple reload 10 is operably engaged to a handleassembly (not shown) of a surgical stapling device or a robotic surgicalsystem, the staple reload 10 is actuated to move the tool assembly 20from the open position (FIG. 1 ) to the closed position (FIG. 11 ) abouttissue. The first firing shaft 24 of the drive assembly 22 translatesdistally while carrying the second firing shaft 28 therewith. Since theclamping member 30 is coupled to the second firing shaft 28, theclamping member 30 advances into engagement with cam surfaces 44 a, 44 b(FIGS. 9 and 12 ) on the channel 44 and/or the anvil 34. The clampingmember 30 is advanced a predetermined distance to move the tool assembly20 to the closed position.

As the anvil 34 and cartridge assembly 36 approximate, the extension 92,94 of the first and second latch arms 80, 82 of the locking member 74enter the respective first and second slots 62, 64 of the anvil 34 viathe entry opening 68 of the slots 62, 64. At this stage, the lockingmember 74 is not yet preventing the tool assembly 20 from opening. Upontraveling the predetermined distance to close the tool assembly 20, theclamping member 30 abuts the proximal end portion 78 a of the elongateelement 78 of the locking member 74 (FIG. 12 ). In addition, uponclosing the tool assembly 20, the protrusion 90 (FIG. 10 ) of theclamping member 30 enters the opening 86 in the elongate element 78 ofthe locking member 74. Accordingly, further advancement of the clampingmember 30 causes the locking member 74 to advance from a proximalposition to a distal position.

In the proximal position, as shown in FIG. 11 , the extensions 92, 94(FIG. 10 ) of the first and second latch arms 80, 82 of the lockingmember 74 are disposed proximally of the support ledges 72 of the anvil34. As the locking member 74 moves to the distal position, theextensions 92, 94 of the first and second latch arms 80, 82 of thelocking member 74 traverse the longitudinal section 70 of the first andsecond slots 62, 64 and engage the support ledges 72, as shown in FIGS.13 and 14 . When the first and second latch arms 80, 82 engage thesupport ledges 72 of the anvil 34, opening of the anvil 34 and cartridgeassembly 36 is resisted, thereby setting a gap distance between theanvil 34 and cartridge assembly 36.

After the clamping member 30 advances the locking member 74 to thedistal, locking position, the clamping member 30 is stopped from furtheradvancing to the tissue-contacting surfaces/through the staple cartridge44 of the tool assembly 20 by a distal limit of the slot 32 (FIG. 2 )defined in the anvil 34. As described above, the second firing shaft 28disengages the first firing shaft 24, allowing the first firing shaft 24and the sled 26 to advance through the staple cartridge 48 independentlyof the clamping member 30 to eject staples from the staple cartridge 48.

After the sled 26 traverses to the distal end portion 36 b of thecartridge assembly 36, the sled 26 may be retracted by retracting thefirst firing shaft 24. As the first firing shaft 24 retracts, the sled26 engages the clamping member 30, whereby the clamping member 30 ismoved proximally. Since the protrusion 90 of the clamping member 30 isreceived in the opening 86 in the elongate element 78 of the lockingmember 74, retraction of the clamping member 30 drives a retraction ofthe locking member 74. As the locking member 74 retracts, the first andsecond latch arms 80, 82 moves proximally within the respective firstand second slots 62, 64 of the anvil 34 to disengage the extension 92,94 of the first and second latch arms 80, 82 from the support ledge 72of the anvil 34. With the locking member 74 of the cartridge assembly 36out of locking engagement with the anvil 34, the tool assembly 20 is nolonger prevented from moving out of the closed position.

FIGS. 15-22 illustrate another embodiment of a locking member 174 forsetting the tissue gap of a tool assembly 120. The tool assembly 120 issimilar to tool assembly 20 and will only be described in detail todescribe differences between the two assemblies.

The tool assembly 120 includes an anvil 134 and a cartridge assembly 136movably coupled to one another. The anvil 134 defines a slot 162 thatextends through the distal end portion 134 b thereof. The distal endportion 134 b of the anvil 134 has a support ledge 172 that partiallydefines the slot 162. The cartridge assembly 136 includes a clampingmember 130 disposed at the proximal end portion 136 a thereof, a lockingmember 174 disposed at the distal end portion 136 b thereof, and anelongated locking plate 178 interconnecting the clamping member 130 andthe locking member 174.

The locking plate 178 is slidably coupled to the cartridge assembly 136and defines a proximal slot 190 in a proximal end portion 178 a of theelongate plate 178, and a distal slot 192 in a distal end portion 178 bof the elongate plate 178. The clamping member 130 is received in theproximal slot 190 and the locking member 174 is received in the distalslot 192. The clamping member 130 is captured within the proximal slot190 of the locking plate 178, such that translation of the clampingmember 130 results in translation of the locking plate 178. The lockingmember 174 may be shaped as an I-beam having a bottom end portion 174 areceived in the distal slot 192 of the elongate plate 178, and a top endportion 174 b configured for receipt in the slot 162 of the anvil 134.The distal slot 192 of the elongate locking plate 178 is sized to allowfor relative movement between the locking plate 178 and the bottom endportion 174 a of the locking member 174.

In operation, the clamping member 130 is advanced from a proximalposition, as shown in FIG. 15 , to a first distal position, as shown inFIG. 17 , to move the tool assembly 120 from the open position to theclosed position. As the clamping member 130 moves to the first, distalposition, the locking plate 178 moves with the clamping member 130 apredetermined distance. Since the distal slot 192 is longer than thebottom end portion 174 a of the locking member 174 (FIG. 16 ), theinitial distal translation of the elongate plate 178 during closing ofthe tool assembly 120 does not result in translation of the lockingmember 174.

Upon closing the tool assembly 120, as shown in FIG. 18 , the top endportion 174 b of the locking member 174 is received in the slot 162 inthe anvil 134. In this position, the anvil 134 and cartridge assembly136 remain separable from one another. The clamping member 130 isfurther advanced, thereby advancing the elongate plate 178 intoengagement with the bottom end portion 174 a of the locking member 174,as shown in FIGS. 18 and 19 . With the elongate plate 178 abutting thebottom end portion 174 a of the locking member 174, further advancementof the elongate plate 178 via the advancing clamping member 130 drivesthe locking member 174 distally, whereby the top end portion 174 b ofthe locking member 174 traverses the slot 162 in the anvil 134 andengages the support ledge 172, as shown in FIG. 20 . With the top endportion 174 b of the locking member 174 disposed on the support ledge172 of the anvil 134 and the bottom end portion 174 a of the lockingmember 174 disposed on the elongate plate 178 of the cartridge assembly136, separation of the tool assembly 120 out of the closed position isresisted.

With reference to FIGS. 21 and 22 , to allow for separation of the anvil134 and cartridge assembly 136 from one another, the clamping member 130is retracted, whereby the elongate plate 178 ultimately engages thebottom end portion 174 a of the locking member 174. Further retractionof the elongate plate 178, via the clamping member 130, proximallytranslates the locking member 174 relative to the anvil 134 to disengagethe top end portion 174 b of the locking member 174 from the supportledge 172 of the anvil 134. With the locking member 174 disengaged fromthe anvil 134, further retraction of the clamping member 130 moves thetool assembly 120 from the closed position to the open position.

FIGS. 23-26 illustrate another embodiment of a locking member 260 forsetting the tissue gap of a tool assembly 220. The tool assembly 220 issimilar to tool assembly 20 and will only be described in detail todescribe differences between the two assemblies.

The tool assembly 220 includes an anvil 234 and a cartridge assembly 236movably coupled to one another. The anvil 234 defines a slot 262 thatextends through a distal end portion 234 b thereof. The distal endportion 234 b of the anvil 234 has a cam surface 270 leading to asupport ledge 272 that together partially define the slot 262. The camsurface 270 is angled proximally so that the support ledge 272 overhangsan entry opening 268 of the slot 262.

The cartridge assembly includes a locking member 274 pivotably supportedin the distal end portion 236 b of the cartridge assembly 236. Thecartridge assembly 236 includes a biasing member 278 (e.g., a torsionspring) coupled to a bottom end portion 274 a of the locking member 274and an engagement surface 280 of the cartridge assembly 236. The biasingmember 278 is configured to resiliently bias the locking member 274toward a locking position, in which the locking member 274 isperpendicular to a longitudinal axis defined by the cartridge assembly236. The locking member 274 includes a top end portion 274 b having anextension 290 configured to be supported on the support ledge 272 of theanvil 234 to prevent the anvil 234 and cartridge assembly 236 frommoving out of the closed position. The tool assembly 220 furtherincludes a sled 226 (FIGS. 25 and 26 ), similar to the sled 26 describedabove, slidably supported in the cartridge assembly 236 for ejectingstaples from the cartridge assembly 236.

In operation, as the tool assembly 220 moves from the open position, asshown in FIG. 23 , toward a partially closed position, as shown in FIG.24 , the top end portion 274 a of the locking member 274 engages the camsurface 270 of the anvil 234. The cam surface 270 pivots the lockingmember 274 out of the locking position, in the direction indicated byarrow “A” in FIG. 24 , against the bias of the biasing member 278. Asthe anvil 234 and cartridge assembly 236 move toward the fully closedposition, as shown in FIG. 25 , the protrusion 290 of the locking member274 passes further into the slot 262 of the anvil 234 and passed thesupport ledge 272. The biasing member 278 pivots the locking member 274about the bottom end portion 274 a thereof, in the direction indicatedby arrow “B” in FIG. 25 , to engage the protrusion 290 of the lockingmember 274 with the support ledge 272 of the anvil 234. In thisposition, the locking member 274 resists separation of the anvil 234 andcartridge assembly 236 from one another.

With reference to FIGS. 25 and 26 , the sled 226 advances through thecartridge assembly 236 until it ejects all of the staples in the distalend portion 236 b of the cartridge assembly 236, whereupon the sled 226engages the bottom end portion 274 a of the locking member 274. Thelocking member 274 rotates in the direction indicated by arrow “A” outof the locking position to disengage the protrusion 290 of the lockingmember 274 from the support ledge 272 of the anvil 234. With the lockingmember 274 disengaged from the support ledge 272 of the anvil 234,movement of the anvil 234 and cartridge assembly 236 out of the closedposition is permitted.

While the tool assemblies described herein are shown in the drawings aslinear tool assemblies, it is contemplated that the tool assemblies maybe configured as curved tool assemblies with similar components andmethods of operation.

Persons skilled in the art will understand that the devices and methodsspecifically described herein and illustrated in the accompanyingdrawings are non-limiting exemplary embodiments. It is envisioned thatthe elements and features illustrated or described in connection withone exemplary embodiment may be combined with the elements and featuresof another without departing from the scope of this disclosure. As well,one skilled in the art will appreciate further features and advantagesof the disclosure based on the above-described embodiments. Accordingly,the disclosure is not to be limited by what has been particularly shownand described, except as indicated by the appended claims.

What is claimed is:
 1. A tool assembly comprising: an anvil having aproximal portion and a distal portion, the distal portion of the anvildefining a slot therein; a cartridge assembly having a proximal portionand a distal portion, the proximal portion of the cartridge assemblypivotably coupled to the proximal portion of the anvil such that theanvil and the cartridge assembly can pivot in relation to one anotherbetween an open position and a closed position; a locking member movablysupported on the distal portion of the cartridge assembly, wherein thelocking member is configured to move within the slot into lockingengagement with the anvil in response to pivotable movement of the anviland the cartridge assembly in relation to one another from the openposition to the closed position to set a gap distance between the distalportions of the anvil and the cartridge assembly, wherein the lockingmember is configured to pivot relative to the cartridge assembly intolocking engagement with the anvil in response to the anvil and thecartridge assembly moving toward the closed position; and a sledslidably supported in the cartridge assembly and configured to ejectstaples from the cartridge assembly, wherein the sled is configured toengage the locking member to pivot the locking member out of lockingengagement with the anvil after the anvil and the cartridge assemblymove to the closed position.
 2. The tool assembly according to claim 1,further comprising a biasing member coupled to the locking member forresiliently biasing the locking member into locking engagement with theanvil.
 3. The tool assembly according to claim 1, wherein the distalportion of the anvil has a cam surface and a support ledge, the camsurface being configured to move the locking member as the anvil andcartridge assembly transition toward the closed position.
 4. The toolassembly according to claim 3, further comprising a biasing membercoupled to the locking member, wherein the biasing member is configuredto pivot the locking member onto the support ledge when the anvil andthe cartridge assembly move in relation to one another from the openposition to the closed position.
 5. The tool assembly according to claim3, wherein the locking member includes: a top end portion including anextension configured to be supported on the support ledge of the anvilto prevent the anvil and the cartridge assembly from moving in relationto one another from the closed position towards the open position; and abottom end portion supported in the cartridge assembly.
 6. The toolassembly according to claim 5, wherein the bottom end portion of thelocking member is pivotably supported by the cartridge assembly.
 7. Thetool assembly according to claim 1, wherein the locking member isperpendicular relative to a longitudinal axis defined by the cartridgeassembly.
 8. A tool assembly comprising: an anvil having a proximalportion and a distal portion, the distal portion of the anvil defining aslot therein; a cartridge assembly having a proximal portion and adistal portion, the proximal portion of the cartridge assembly pivotablycoupled to the proximal portion of the anvil such that the anvil and thecartridge assembly are transitionable between an open position and aclosed position; a locking member including: a bottom end portionpivotably supported by the distal portion of the cartridge assembly; anda top end portion configured for locking engagement with the anvil toset a gap distance between the anvil and the cartridge assembly when theanvil and cartridge assembly are in the closed position; and a sledslidably supported in the cartridge assembly from a sled retractedposition to a sled advanced position to sequentially eject staples fromthe cartridge assembly, wherein the sled is configured to engage thelocking member to pivot the locking member within the slot out oflocking engagement with the anvil when the actuation sled is moved tothe sled advanced position.
 9. The tool assembly according to claim 8,further comprising a biasing member coupled to the locking member forresiliently biasing the locking member into locking engagement with theanvil.
 10. The tool assembly according to claim 9, wherein the distalportion of the anvil has a cam surface and a support ledge, the camsurface being configured to pivot the locking member against theresilient bias of the biasing member as the anvil and cartridge assemblytransition toward the closed position.
 11. The tool assembly accordingto claim 10, wherein the biasing member is configured to move the topend portion of the locking member onto the support ledge when the anviland the cartridge assembly transition to the closed position.
 12. Thetool assembly according to claim 11, wherein the top end portion of thelocking member has a lateral extension configured to be supported on thesupport ledge of the anvil to prevent the anvil and the cartridgeassembly from moving out of the closed position.
 13. The tool assemblyaccording to claim 8, wherein the locking member is perpendicularrelative to a longitudinal axis defined by the cartridge assembly.